摘要
An earthquake with M7. 1 occurred in Yushu,Qinghai Province,China,at 07:49 a. m. on April 14,2010,according to the Chinese Seismic Station Network. The sequence is a fore-mainafter-shock type sequence. A foreshock with M4. 7 occurred 2 hours and 11 minutes before the main shock. There were 12 foreshocks and 2385 aftershocks until June 31,2010. In which,there are 21 aftershocks between M3. 0 and M3.
An earthquake with M7.1 occurred in Yushu, Qinghai Province, China, at 07：49 a.m. on April 14, 2010, according to the Chinese Seismic Station Network. The sequence is a fore-main- after-shock type sequence. A foreshock with M4.7 occurred 2 hours and 11 minutes before the main shock. There were 12 foreshocks and 2385 aftershocks until June 31 , 2010. In which, there are 21 aftershocks between M3.0 and M3.9, 8 aftershocks between M4.0 and M4.9, 2 aftershocks between M5.0 and M5.9, and 1 aftershock between M6. 0 and M6. 9. The strongest aftershock is the Yushu earthquake with M6.3 at 09..25 a.m. on Aoril 14. 2010 （Table 1 ）.
